The reduction of nitroarenes is usually catalyzed by heterogeneous catalysts. In this work, highly stable aqueous dispersions of monodisperse Pt, Pd, and Au nanoparticles stabilized by thermosensitive polymer, poly(N-isopropylacrylamide) (PNIPAM), are conveniently synthesized with the average sizes of 2.3, 3.1, and 2.3 nm, respectively. The modulation of the hydrophilic-hydrophobic nano-environments of the catalysts can be selectively provided by utilizing the temperature-responsive characteristics of PNIPAM. They are effective and thermosensitive pseudohomogeneous catalysts for nitroarenes reduction. The decreasing trend of catalytic activity is as follows: PNIPAM-Au > PNIPAM-Pd > PNIPAM-Pt. The catalytic reduction of nitrobenzene (NB), 4-nitrophenol (4-NP), and o-nitroaniline (o-NA) follow the pseudo-first-order kinetics, and the catalytic rates can be tuned by utilizing their temperature-responsive behavior. PNIPAM-Au nanocatalysts exhibit high turnover frequencies (TOF) up to 84, 12.9, and 40 min⁻¹ for catalytic reduction of NB, 4-NP, and o-NA at 20 °C, respectively, which are one of the highest values ever reported.

硝基芳烃的还原通常由多相催化剂催化。在这项工作中，由热敏聚合物聚（N-异丙基丙烯酰胺）（PNIPAM）稳定的单分散 Pt、Pd 和 Au 纳米粒子的高度稳定的水分散体被方便地合成，平均尺寸分​​别为 2.3、3.1 和 2.3 nm。通过利用 PNIPAM 的温度响应特性，可以选择性地调节催化剂的亲水-疏水纳米环境。它们是用于硝基芳烃还原的有效且热敏的拟均相催化剂。催化活性的下降趋势如下：PNIPAM-Au > PNIPAM-Pd > PNIPAM-Pt。硝基苯 (NB)、4-硝基苯酚 (4-NP) 和邻硝基苯胺 (o-NA) 的催化还原遵循拟一级动力学，并且可以通过利用它们的温度响应行为来调整催化速率。PNIPAM-Au 纳米催化剂表现出高达 84、12.9 和 40 分钟的高周转频率 (TOF)^{-1 分别}用于在 20 °C 下催化还原 NB、4-NP 和 o-NA，这是有史以来报告的最高值之​​一。